**about 3 years ago** - No comments

Wow, it is a long time since I posted here. So much to do, so little time!

I might as well keep it brief now, then. Here’s a puzzle for April 1st (it’s actually a normal puzzle without tricks – it just spells ‘FOOL’ in the given numbers). Place 1 to 9 in each row, column More >

**about 4 years ago** - No comments

Sudoku Box-Jigsaw 9×9 1 puzzleI haven’t posted a puzzle for a good while, so I thought it was time to fix that with this Box-Jigsaw Sudoku puzzle.

The puzzle combines regular Sudoku with Jigsaw Sudoku. Just place 1 to 9 once each into all of the nine rows, columns, 3×3 boxes (indicated by both shaded and More >

**about 4 years ago** - No comments

A brand new book, packed with 101 Jumbo 3D Sudoku, is now available for purchase from Amazon. You can either search for this directly, or you can click through via my PuzzleBooks.org site – the book is at the very bottom of that page, and clicking on it will take you direct to the correct More >

**about 4 years ago** - No comments

Jumbo 3D sudoku puzzleI haven’t posted for a while so I thought I should post one of my new puzzles. This one is a Jumbo 3D Sudoku, where the aim is simply to place 1 to 9 into each black-lined 3×3 area as well as each of the 54 rows indicated by the coloured lines. More >

**about 4 years ago** - No comments

Product Killer Sudoku 9×9 puzzle

If you’re interested in sudoku, come along to the official UK sudoku championship next weekend, the 29th-30th of March, at Selsdon Park Hotel just south of London, outside Croydon. There’s full details on the UK Puzzle Association site. There’s still spaces available.

Mind you, it’s not just sudoku – there’s also the More >

**about 4 years ago** - No comments

Valentine SudokuA quick heart-shaped sudoku for Valentine’s Day. Just place 1 to 9 once each in every row, column and bold-lined box.

**about 4 years ago** - No comments

Sudoku Xtra 24 is now finally available! It’s packed with 130 puzzles of a wide range of types, including a huge variety of sudoku variants.

This issue I’ve included a very wide range

of variants, including some new ones such as Two-grid Interconnected Sudoku, Mystery Multiple

Sudoku and Blackout Sudoku. Meanwhile I’ve made an effort to include More >

**about 4 years ago** - No comments

Sudoku Christmas Star puzzleA Sudoku, in a star shape.

Just that. (Place 1-9 once each into every row, column and bold-lined 3×3 box).

**about 5 years ago** - No comments

I’ve recently launched a new series of ‘101 Giant Sudoku’ books, to cater for those who like their Sudoku to be considerably larger than normal!

You can see the entire series at PuzzleBooks.org (scroll to the bottom) or visit Amazon and search for “101 giant sudoku”.

There are currently 12 books in the series: 14×14, 15×15, 16×16, 18×18, More >

**about 6 years ago** - No comments

Just a quick heads-up that PuzzleMix, my site where you can play a wide range of puzzles online, now supports touch screen play for all of the number entry puzzles – so that’s Sudoku, Killer Sudoku, Futoshiki, Calcudoku, Skyscraper, Sudoku X, Kropki Sudoku, Killer Sudoku Pro, Jigsaw Sudoku, Consecutive Sudoku, Wraparound Sudoku, Sudoku XV, Killer More >

Spittledungabout 9 years ago

Nice change. Not hard. Division cages feel as if they will be very easy to deduce since the dividend can’t be above 9 in value.

I would call this puzzle “MathDoku”. In the case of generating more interest, that would be like calling sushi “Cold Raw Fish” since many hear the word maths and flee. … but I still like the name.

Laineabout 8 years ago

Am i missing something? Spittledung says it’s not hard, but look at the bottom RH box – it doesn’t work!

Single box 8 must contain 8

9x can only be 1×9 (3×3 is not allowed)

24x can only be 2×3x4 (anything else needs a 1 – already used for 9x – or uses a single digit twice)

10x can only be 2×5 and as 24x contains 2, the 2 of 10x must be in he middle bottom box and the 5 in the bottom right box

So now, in the bottom right box, we have 1,2,3,4,5,8,9, and we have 2 empty boxes – where to place the 6 & 7?

The 7 can’t go in the 3- box because that would require a 10 from which to deduct 7 to get 3. So the 6 has to go in the 3- box … but wait a minute, that means the other digit has to be 9: 9-6=3 right? But there is already a 9 in the bottom row….

Or, as I said, am I missing something?

Spittledungabout 8 years ago

Minus signs are tricky in KenKen type puzzles…

It has been a while since I have done this puzzle, but the glitch in the logic above comes with the 3- cage. You say that the 7 can’t go into this cage, but it could be 7 and the other number being a 4 (7-4=3). Likewise the 6 might work with the other number being a 3 (6-3=3). Further solving needs to be done…

I believe the something you might be missing is that the digits can be in any order for subtraction cages so long as the bigger number minus the smaller number gives the result, For the 0- cage in the same region, the biggest number in the cage minus the other two combined give 0.

It is always great to see others commenting about puzzles. Please stick around Laine.

Laineabout 8 years ago

Hi there Spittledung!

Can’t have 7-4 or 6-3 in the 3- cage, that would put the 4 or the 3 in the square and the 24x cage already has both 3 & 4 in it!

I’ve got so hooked on the “all signs” Sudoku

Spittledungabout 8 years ago

I believe that you missed the point in my previous post…

The larger number does NOT have to be the first one in the 3- cage (the one on the left). So by your deductions above it IS possible to have “4 (on the left) and 7 (in the region which you are deducing)” or “3 (on the left) and 6 (in the region which you are deducing)”.

So it is possible to have either 4_7 or 3_6. Now continue solving….

Laineabout 8 years ago

Aha! Now I see I thought that as division & subtraction aren’t commutative, the larger number(s) had to go first, and this is the first puzzles I’ve done where my assumption hasn’t worked!

Live & learn

Thanks for your explanations, now let’s see if I can solve the rest of the puzzle…

about 8 years ago

The largest number DOES have to go first. It’s just that it doesn’t matter what order you write them in the grid. Pick the largest number from the cage and use that first, then subtract or divide by the other numbers in the cage.

Hope this helps!

Jeanette Dysonabout 7 years ago

I love Killer Sudoku puzzles and at the weekend there was a Killer Sudoku Pro in The Telegraph. I have yet to attempt yours above but wonder if you have any more I can try. I only like the Killer types. Thanks for your time. These are fab !!! Jeanette )

about 7 years ago

There are more of these in each issue of my Sudoku Xtra magazine – take a look at http://www.sudokuxtra.com.

There are also loads of other puzzles too, of course! (And not just Sudoku variants)